From owner-freebsd-questions Wed Oct 27 12:38:17 1999 Delivered-To: freebsd-questions@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by hub.freebsd.org (Postfix) with ESMTP id 464CD14F0F; Wed, 27 Oct 1999 12:38:07 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id MAA35962; Wed, 27 Oct 1999 12:38:04 -0700 (PDT) (envelope-from dillon) Date: Wed, 27 Oct 1999 12:38:04 -0700 (PDT) From: Matthew Dillon Message-Id: <199910271938.MAA35962@apollo.backplane.com> To: "Ronald G. Minnich" Cc: Ilia Chipitsine , Chuck Youse , questions@FreeBSD.ORG, hackers@FreeBSD.ORG Subject: Re: why FFS is THAT slower than EXT2 ? References: Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :On Wed, 27 Oct 1999, Ilia Chipitsine wrote: :> as far as I remember ext2 has some "counter". I used to use Linux and :> it performed 'fsck' from time to time (even if fs was clearly unmounted). :> that is a very good thing to have. : :And it's a good thing because ... well, maybe because it's not that :reliable an FS. I actually can't see it as a good thing if you have a file :system that doesn't need it. : :> I do not recall that FreeBSD did such thing. : :It might not have needed to. It never has in five years for me. : :The numbers are from my old job at sarnoff, see my web page ... for a :while in 1997-99 we had "things go wrong" about once a month. Over the :space of 18 months as "things went wrong" we found ourselves having to fix :at least one Linux box each time. On average it was four. : :> I DID lose FFS even it was mounted "sync", not async. : :I guess I was lucky :-) : :anyway, I'll drop this thread, just trying to fill in some info. : :ron To be fair, the counter gizmo for ext2fs was from a time many years ago when ext2fs was not all that reliable. I believe ext2fs has gotten quite a bit more reliable in the last year though. Also it is no longer as simple as it was originally. It turns out there's a reason for UFS/FFS's complexity. The linux crowd has similar problems with their 'simpler' swap and VM subsystems. But before people start smirking keep in mind that linux is quite a bit farther ahead of us in the SMP department. When Kirk gets his softupdates/filesystem-checkmarking code working we are going to be a step up from anything linux could hope to accomplish in the filesystem arena because we will then be able to reliably dump, checkmark, AND sanity-check the filesystem on a live (and busy) system. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message